Abstract TP147: Relationship Between Carotid Artery Atherosclerosis and Hyoid Anatomy: Results From a Cross-sectional and Longitudinal Cohort Study

Abstract

Background: Asymmetric internal carotid artery (ICA) plaque is common and are not fully explained by carotid geometry. Case reports have identified an increased risk of ICA injury and atherosclerosis with shorter hyoid wing-ICA distances. However, this relationship has not been characterized on a population level. Hypothesis: Shorter hyoid-ICA distances will be associated with greater ICA plaque and accelerated plaque formation over time. Methods: Retrospective cross-sectional and longitudinal cohort designs were used to evaluate consecutive adult patients at 3 hospitals who underwent 2 computed tomography angiography (CTA) studies of the neck ≥2 years apart (01/2000-07/2017). Patients with pre-existing neck or ICA surgery, dissection, or occlusion were excluded. Moderate ICA plaque (≥3mm), plaque characteristics, and stenosis at the level of the greater hyoid wing were compared by hyoid-ICA distance; and comparisons were made over time. Results: Sixty-six patients were included, with a median age of 64 years (IQR 53-73), 37 (56.1%) female, and 28 (42.4%) non-white. The median hyoid-ICA distance was 3.06mm (IQR 1.27-6.20mm), and when the hyoid-ICA distance was less than the median, moderate plaque was not more common (53.0% vs. 48.5%, p=0.601), and this remained non-significant after multivariable adjustment (OR 0.88, 95%CI 0.37-2.07, p=0.765) or when analyzed by hyoid-ICA distance quartile (adjusted p=0.586; Figure 1A). After a median follow-up of 1002 days (range 392-3,397 days), the odds of plaque progression (increase by ≥0.5mm) were not significantly greater when the hyoid-ICA distance was less than the median (adjusted OR 0.74, 95%CI 0.30-1.83, p=0.513), or when compared across distance quartiles (adjusted p=0.795; Figure 1B). Conclusion: In this cross-sectional and longitudinal cohort study, there was no association between hyoid wing proximity and ICA plaque thickness or stenosis.